The candidates in one of the country's tightest Senate races disagreed on a strategy for the war in Iraq in their last of three debates Saturday.

Democratic Rep. Harold Ford Jr. said he wants to "chart a new course in Iraq" by dividing the country into three autonomous states that would share control over international borders.

Republican Bob Corker disagreed, saying: "If we can't cause a county to come together in one, I know we can't do it dividing it in three."

The result of the race, which polls show is tight, could determine which party controls the Senate next year. Ford, who is trying to become the first black senator elected from the South since Reconstruction, has tried to portray himself as more knowledgeable on federal and foreign policy than Corker, a former mayor of Chattanooga.

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The debate follows a flap this week over a Republican National Committee-financed television ad that showed a white woman saying she met Ford at a Playboy-sponsored party. The ad ends with the woman, her bare shoulders visible, looking into the camera and whispering, "Harold, call me."

The ad does not mention that Ford is black, but Democrats said it attempted to evoke deep-seated prejudices about interracial dating.

The candidates were questioned about the advertisement but spoke only briefly about it.

"As far as negative ads, I don't like them, either," Corker said, adding that he has asked for independently financed ads like the Playboy ad not to air. "I'd like my opponent to join me in asking that all of these ads come down," he said.

Ford said he wouldn't care if all negative ads by independent organizations were taken off the air.

"If there was an ad that ran like the one that ran here ... if anyone I knew or may have been associated with had anything to do with it, that ad would have been down an hour after I learned (about it)," Ford said.

Corker, who called for the ad to be pulled, has deemed it "tacky," while Ford has called it "smutty." Neither would say whether they think it is racist.

The candidates were asked about personal savings accounts and Social Security. President Bush, who pledged an overhaul of Social Security, has failed to make headway in Congress with a plan to offer private savings accounts to younger workers.

Corker said he thought personal accounts would work after Social Security's funding system was stabilized.

Ford suggested that rich people should not be paid Social Security benefits if it puts the system at risk.

Corker continued to characterize the Memphis congressman as a "Washington insider," but he refrained from talking about Ford's large, politically active family, which he has called a "political machine" in previous debates. He has questioned Ford's professional relationship with his father, former U.S. Rep. Harold Ford Sr., now a lobbyist.

Corker emphasized his Tennessee background in his opening comments. He has tried to depict Ford as a Washington insider with tenuous Tennessee connections. Ford, 36, moved to Washington when he was 9 because his father was serving in Congress.

Ford has countered, saying his opponent is "not even from Tennessee — he's from South Carolina."

Corker, 54, was born in Orangeburg, S.C., and moved to Tennessee when he was 11.

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